smartmap

library(smartmap)

smartmap produces interactive maps from a variety of R objects with minimal coding required. This makes it great for previewing spatial data. It provides only three functions:

• smap(): The core function. Smartly create leaflet maps from R objects. Maps created with smap() contain two dialogues in the top right corner: one for switiching the background map and one for measuring distances and areas.
• smart_as_sf(): Applies the same heuristics as smap(), but returns sf objects instead.
• as_coord_matrix: Applies the same heuristics as smap(), but returns a numeric matrix with longitude and latitude instead.

Data frames

Viewing data.frames with longitude and latitude columns was the basic use case for which smartmap was created. The heuristics for automatically determining the geo-coordinate columns are simple, but should work for most use cases.

print(cities)
smap(cities)

#>              city LaTituDE       lng       pop country         province
#> 1         Bregenz 47.51670  9.766702   26928.0 Austria       Vorarlberg
#> 2      Eisenstadt 47.83330 16.533297   13165.0 Austria       Burgenland
#> 3 Wiener Neustadt 47.81598 16.249954   60621.5 Austria Niederösterreich
#> 4            Graz 47.07776 15.410005  242780.0 Austria       Steiermark
#> 5      Klagenfurt 46.62034 14.310020   88588.0 Austria          Kärnten
#> 6            Linz 48.31923 14.288781  265161.5 Austria   Oberösterreich
#> 7        Salzburg 47.81048 13.040020  178274.0 Austria         Salzburg
#> 8       Innsbruck 47.28041 11.409991  133840.5 Austria            Tirol
#> 9          Vienna 48.20002 16.366639 2065500.0 Austria             Wien

source: World Cities Database

Shapefiles

smap() also works with file system paths or urls to shapefiles. It even looks inside zip files if necessary!

smap("https://www.naturalearthdata.com/http//www.naturalearthdata.com/download/50m/cultural/ne_50m_admin_0_countries.zip")

Point coordinates

Numeric vectors of length 2 are interpreted as longitude/latitude coordinate pairs. If you supply names, smap uses them to identify the correct order.

smap(c(16.422524, 48.185686))
smap(c(LAT = 48.185686, LoNgItuDE = 16.422524))

Leaflet maps

You can call smap() on existing leaflet objects to add background tiles and a ruler for measuring distance

library(leaflet)
lf <- leaflet::leaflet(height=200) %>% 
  leaflet::addCircleMarkers(lng = 16.422524, lat = 48.185686)

lf
smap(lf)

Simple features (sf)

Everyone who has worked with simple features will know that it is sometimes a bit awkward to convert between the different datatypes provided by the package (sf::sf, sf::sfc and sf::sfg). Toe remedy this smap() works natively with all three.

smap(sf::st_point(c(16.373311, 48.208482)))
smap(sf::st_sfc(sf::st_point(c(16.373311, 48.208482))))
smap(sf::st_sf(coords = sf::st_sfc(sf::st_point(c(16.373311, 48.208482))), crs = 4326))